The present invention broadly relates to a method of and apparatus for treating cotton flocks at an early stage of cotton processing and, more specifically, pertains to a new and improved method of reducing the stickiness or tackiness of the fibers of cotton flocks contaminated with honeydew. The present invention also relates to a new and improved apparatus for reducing the stickiness of the fibers of honeydew-contaminated cotton flocks.
Generally speaking, the present invention relates to a new and improved method of the type hereinbefore described and which method entails heating the honeydew-contaminated cotton flocks.
It is known that cotton flocks of certain provenances or origins are contaminated or coated to varying degrees with sugar-containing secretions from insects. These secretions containing sugar are generally known as honeydew. A large number of proposals have been made as to how honeydew can be made to caramelize by heating cotton flock samples for the purpose of determining the degree of honeydew contamination from the resulting change in the color of the cotton flocks. This is namely very important because in the event of considerable contamination, the cotton flocks become sticky or tacky and tend to stick or adhere to various parts of the yarn production plant or to form laps or coils at rolls or rollers or other rotatable members, this being very undesirable since it results in frequent interruption of the yarn manufacturing process and in an inferior yarn.
A method of the aforementioned type is already disclosed in European Patent Application No. 86.102352.1, published Oct. 8, 1986 under European Patent Publication No. 196,449. The object of this known method is to convert any contaminating honeydew into a non-sticky or non-tacky and brittle state or condition by supplying heat for a short period of time and preferably without causing any discoloration or change in the color of the cotton flocks, so that the brittle sugar deposits can be crushed and removed in the course of subsequent processing.
A number of devices or apparatuses for performing this prior art method have been proposed in the abovementioned European Patent Application No. 86.102352.1, published under European Patent Publication No. 196,449. One device or apparatus is intended to heat the fiber flocks before the actual opening of the raw cotton bales, i.e. directly at the start of the yarn manufacturing process. On the other hand, other devices or apparatuses are intended for treating fiber slivers between the card and drafting arrangement or during drafting.
In spinning mills, in which the cotton spun is heavily contaminated with honeydew, efforts are made to keep the ambient air moisture or humidity very low, and experience has shown that this results in reduction of the frequency of interruptions in the yarn manufacturing process. However, the very low air humidity is undesirable as such, since the cotton fibers suffer mechanical damage during yarn manufacture such that the yarn quality is not at an optimum although the best types of cotton in terms of quality originate from provenances where the honeydew contamination is quite considerable. Also, very dry air causes problems with regard to electrostatic charges which result, for example, in undesirable accumulations of fly fibers. Furthermore, in the case of a very low air humidity, the operating staff or personnel finds the climatic conditions inside the spinning mill unpleasant.
As a result of such difficulties many yarn manufacturers first wash the cotton flocks in order to remove the honeydew deposits. However, washing is not only expensive, but also results in reduction or deterioration of yarn quality.
Since only some types of cotton or deliveries of cotton are contaminated with honeydew, the installation of special continuous treatment plants, for instance in accordance with the disclosure of the aforesaid European Patent Application No. 86.102352.1, published under European Patent Publication No. 196,449, is in many cases undesirable, particularly since there is frequently no space at all for any subsequent installation.